It was a fourth league win on the trot for Guardiola's outfit, who are building momentum and can continue to crank up the heat up on their title rivals when they face Stoke in a game in hand on Wednesday.

But they are fighting on three fronts, with this routine victory marking the start of five games in 15 days that include a Champions League last-16 second-leg trip to Monaco and a FA Cup quarter-final at Middlesbrough.

It is a problem Guardiola will welcome, but does the Spaniard's squad have the depth to cope?

He made five changes to the side which thrashed Huddersfield 5-1 in midweek and could afford to drop Kevin de Bruyne for Silva, whose incisive passing helped unlock a resilient Sunderland.

Aguero proves his worth

So what about Aguero? The Argentine's future was thrust into the spotlight after he lost his place to 19-year-old Gabriel Jesus last month, and he admitted this week his position at the club was unclear.

Guardiola can be ruthless when he feels a player does not fit into his system, just ask Joe Hart, but a metatarsal injury for Brazil forward Jesus appears to have offered Aguero a lifeline.

The 28-year-old has now scored five goals in his last three games in all competitions for City, having gone six games without finding the net before that.

Sane (left) and Sterling (right) stuck rigidly to their wings for Manchester City, as this heatmap shows

Guardiola is building a team spearheaded by youth, and Aguero's poacher-like presence was complemented once again by the creativity of Sterling and Sane.

Sterling's trickery proved a constant threat down the right and Sane's sheer speed gave City an outlet on the opposite flank, gliding beyond his marker to finish left-footed past Pickford for the visitors' second.

No miracle cure for Moyes

Sunderland have become masters of beating the drop when appearing dead and buried in recent seasons, but they may have left the escape act too late this time around.

Sitting six points from safety at the bottom of the Premier League, the Black Cats' fate lies out of their hands.

And with relegation rivals Crystal Palace, Swansea and Leicester enjoying a recent upturn in form, David Moyes needs something of a miracle if his side are to spring a late recovery.

Moyes' side have taken points off Liverpool and Tottenham at home since the turn of the year, and did frustrate City for long spells in the first half, but once the visitors found a breakthrough they were able to keep Sunderland at arm's length.

Man of the match - David Silva (Man City)

Everything City did went through captain David Silva, who made more passes than any other player in the opposition half (53) and boasted a 94.3% passing accuracy

'I don't like to defend a result at 2-0'

Sunderland manager David Moyes speaking to BBC Sport: "I don't think you can fault the players for any of that. We lacked quality at times though. They did all they could to try to get something out of the game."

On the team: "When you're in it every day you see the levels go up. We've got games coming up - we don't have to show it, we have to do it.

"We tried to make chances. The one that hits the post and comes out maybe that'll hit the inside of the post and go in next time.

"I hope our players understand the position that we're in, but we're not panicking."

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Sunderland 0-2 Manchester City: Pep Guardiola wants team improvement

Manchester City manager Pep Guardiola speaking to BBC Sport: "We are so happy. We played good. We expected aggression and intensity. It was a very good first goal. It was important to go into half-time 1-0 up. If they were winning with the amazing atmosphere it would have been difficult.

"Leroy Sane is every day getting better. He has gaps to improve but he's only 21. He's an intelligent guy and a very nice guy. We are here to help him become what he can be.

"We were passing the ball between ourselves in the last 25 minutes. I don't like to defend a result and be near our box. It is OK if you're 3-0 or 4-0 up but not 2-0."